| 摘要 |
APPARATUS FOR CONTINUOUSLY CONTROLLED EMISSION OF LIGHT FROM PRISM LIGHT GUIDE A variety of techniques are used to effect continuously controlled emission of light from a light guide. For example, the light guide may contain a mechanism formed of a substantially non-light absorptive material having a density which varies as a function of the length of the light guide. The mechanism causes light to escape from the light guide at a rate which varies along the length of the light guide, such that the amount of light escaping, per unit length, along the light guide has a selected distribution of values. Alternatively, the light guide's central path may be nonlinear. As a further alternative, the average crosssectional dimension of each of the plane segments aforesaid may be non-constant. As yet another alternative, a first portion of the light guide may comprise prism light guide material and the remaining portion may be such that a substantial portion of light incident thereupon is allowed to escape therethrough. |
